xref: /openbmc/linux/lib/iomap.c (revision b79de57b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Implement the default iomap interfaces
4  *
5  * (C) Copyright 2004 Linus Torvalds
6  */
7 #include <linux/pci.h>
8 #include <linux/io.h>
9 
10 #include <linux/export.h>
11 
12 /*
13  * Read/write from/to an (offsettable) iomem cookie. It might be a PIO
14  * access or a MMIO access, these functions don't care. The info is
15  * encoded in the hardware mapping set up by the mapping functions
16  * (or the cookie itself, depending on implementation and hw).
17  *
18  * The generic routines don't assume any hardware mappings, and just
19  * encode the PIO/MMIO as part of the cookie. They coldly assume that
20  * the MMIO IO mappings are not in the low address range.
21  *
22  * Architectures for which this is not true can't use this generic
23  * implementation and should do their own copy.
24  */
25 
26 #ifndef HAVE_ARCH_PIO_SIZE
27 /*
28  * We encode the physical PIO addresses (0-0xffff) into the
29  * pointer by offsetting them with a constant (0x10000) and
30  * assuming that all the low addresses are always PIO. That means
31  * we can do some sanity checks on the low bits, and don't
32  * need to just take things for granted.
33  */
34 #define PIO_OFFSET	0x10000UL
35 #define PIO_MASK	0x0ffffUL
36 #define PIO_RESERVED	0x40000UL
37 #endif
38 
39 static void bad_io_access(unsigned long port, const char *access)
40 {
41 	static int count = 10;
42 	if (count) {
43 		count--;
44 		WARN(1, KERN_ERR "Bad IO access at port %#lx (%s)\n", port, access);
45 	}
46 }
47 
48 /*
49  * Ugly macros are a way of life.
50  */
51 #define IO_COND(addr, is_pio, is_mmio) do {			\
52 	unsigned long port = (unsigned long __force)addr;	\
53 	if (port >= PIO_RESERVED) {				\
54 		is_mmio;					\
55 	} else if (port > PIO_OFFSET) {				\
56 		port &= PIO_MASK;				\
57 		is_pio;						\
58 	} else							\
59 		bad_io_access(port, #is_pio );			\
60 } while (0)
61 
62 #ifndef pio_read16be
63 #define pio_read16be(port) swab16(inw(port))
64 #define pio_read32be(port) swab32(inl(port))
65 #endif
66 
67 #ifndef mmio_read16be
68 #define mmio_read16be(addr) swab16(readw(addr))
69 #define mmio_read32be(addr) swab32(readl(addr))
70 #define mmio_read64be(addr) swab64(readq(addr))
71 #endif
72 
73 unsigned int ioread8(const void __iomem *addr)
74 {
75 	IO_COND(addr, return inb(port), return readb(addr));
76 	return 0xff;
77 }
78 unsigned int ioread16(const void __iomem *addr)
79 {
80 	IO_COND(addr, return inw(port), return readw(addr));
81 	return 0xffff;
82 }
83 unsigned int ioread16be(const void __iomem *addr)
84 {
85 	IO_COND(addr, return pio_read16be(port), return mmio_read16be(addr));
86 	return 0xffff;
87 }
88 unsigned int ioread32(const void __iomem *addr)
89 {
90 	IO_COND(addr, return inl(port), return readl(addr));
91 	return 0xffffffff;
92 }
93 unsigned int ioread32be(const void __iomem *addr)
94 {
95 	IO_COND(addr, return pio_read32be(port), return mmio_read32be(addr));
96 	return 0xffffffff;
97 }
98 EXPORT_SYMBOL(ioread8);
99 EXPORT_SYMBOL(ioread16);
100 EXPORT_SYMBOL(ioread16be);
101 EXPORT_SYMBOL(ioread32);
102 EXPORT_SYMBOL(ioread32be);
103 
104 #ifdef readq
105 static u64 pio_read64_lo_hi(unsigned long port)
106 {
107 	u64 lo, hi;
108 
109 	lo = inl(port);
110 	hi = inl(port + sizeof(u32));
111 
112 	return lo | (hi << 32);
113 }
114 
115 static u64 pio_read64_hi_lo(unsigned long port)
116 {
117 	u64 lo, hi;
118 
119 	hi = inl(port + sizeof(u32));
120 	lo = inl(port);
121 
122 	return lo | (hi << 32);
123 }
124 
125 static u64 pio_read64be_lo_hi(unsigned long port)
126 {
127 	u64 lo, hi;
128 
129 	lo = pio_read32be(port + sizeof(u32));
130 	hi = pio_read32be(port);
131 
132 	return lo | (hi << 32);
133 }
134 
135 static u64 pio_read64be_hi_lo(unsigned long port)
136 {
137 	u64 lo, hi;
138 
139 	hi = pio_read32be(port);
140 	lo = pio_read32be(port + sizeof(u32));
141 
142 	return lo | (hi << 32);
143 }
144 
145 u64 ioread64_lo_hi(const void __iomem *addr)
146 {
147 	IO_COND(addr, return pio_read64_lo_hi(port), return readq(addr));
148 	return 0xffffffffffffffffULL;
149 }
150 
151 u64 ioread64_hi_lo(const void __iomem *addr)
152 {
153 	IO_COND(addr, return pio_read64_hi_lo(port), return readq(addr));
154 	return 0xffffffffffffffffULL;
155 }
156 
157 u64 ioread64be_lo_hi(const void __iomem *addr)
158 {
159 	IO_COND(addr, return pio_read64be_lo_hi(port),
160 		return mmio_read64be(addr));
161 	return 0xffffffffffffffffULL;
162 }
163 
164 u64 ioread64be_hi_lo(const void __iomem *addr)
165 {
166 	IO_COND(addr, return pio_read64be_hi_lo(port),
167 		return mmio_read64be(addr));
168 	return 0xffffffffffffffffULL;
169 }
170 
171 EXPORT_SYMBOL(ioread64_lo_hi);
172 EXPORT_SYMBOL(ioread64_hi_lo);
173 EXPORT_SYMBOL(ioread64be_lo_hi);
174 EXPORT_SYMBOL(ioread64be_hi_lo);
175 
176 #endif /* readq */
177 
178 #ifndef pio_write16be
179 #define pio_write16be(val,port) outw(swab16(val),port)
180 #define pio_write32be(val,port) outl(swab32(val),port)
181 #endif
182 
183 #ifndef mmio_write16be
184 #define mmio_write16be(val,port) writew(swab16(val),port)
185 #define mmio_write32be(val,port) writel(swab32(val),port)
186 #define mmio_write64be(val,port) writeq(swab64(val),port)
187 #endif
188 
189 void iowrite8(u8 val, void __iomem *addr)
190 {
191 	IO_COND(addr, outb(val,port), writeb(val, addr));
192 }
193 void iowrite16(u16 val, void __iomem *addr)
194 {
195 	IO_COND(addr, outw(val,port), writew(val, addr));
196 }
197 void iowrite16be(u16 val, void __iomem *addr)
198 {
199 	IO_COND(addr, pio_write16be(val,port), mmio_write16be(val, addr));
200 }
201 void iowrite32(u32 val, void __iomem *addr)
202 {
203 	IO_COND(addr, outl(val,port), writel(val, addr));
204 }
205 void iowrite32be(u32 val, void __iomem *addr)
206 {
207 	IO_COND(addr, pio_write32be(val,port), mmio_write32be(val, addr));
208 }
209 EXPORT_SYMBOL(iowrite8);
210 EXPORT_SYMBOL(iowrite16);
211 EXPORT_SYMBOL(iowrite16be);
212 EXPORT_SYMBOL(iowrite32);
213 EXPORT_SYMBOL(iowrite32be);
214 
215 #ifdef writeq
216 static void pio_write64_lo_hi(u64 val, unsigned long port)
217 {
218 	outl(val, port);
219 	outl(val >> 32, port + sizeof(u32));
220 }
221 
222 static void pio_write64_hi_lo(u64 val, unsigned long port)
223 {
224 	outl(val >> 32, port + sizeof(u32));
225 	outl(val, port);
226 }
227 
228 static void pio_write64be_lo_hi(u64 val, unsigned long port)
229 {
230 	pio_write32be(val, port + sizeof(u32));
231 	pio_write32be(val >> 32, port);
232 }
233 
234 static void pio_write64be_hi_lo(u64 val, unsigned long port)
235 {
236 	pio_write32be(val >> 32, port);
237 	pio_write32be(val, port + sizeof(u32));
238 }
239 
240 void iowrite64_lo_hi(u64 val, void __iomem *addr)
241 {
242 	IO_COND(addr, pio_write64_lo_hi(val, port),
243 		writeq(val, addr));
244 }
245 
246 void iowrite64_hi_lo(u64 val, void __iomem *addr)
247 {
248 	IO_COND(addr, pio_write64_hi_lo(val, port),
249 		writeq(val, addr));
250 }
251 
252 void iowrite64be_lo_hi(u64 val, void __iomem *addr)
253 {
254 	IO_COND(addr, pio_write64be_lo_hi(val, port),
255 		mmio_write64be(val, addr));
256 }
257 
258 void iowrite64be_hi_lo(u64 val, void __iomem *addr)
259 {
260 	IO_COND(addr, pio_write64be_hi_lo(val, port),
261 		mmio_write64be(val, addr));
262 }
263 
264 EXPORT_SYMBOL(iowrite64_lo_hi);
265 EXPORT_SYMBOL(iowrite64_hi_lo);
266 EXPORT_SYMBOL(iowrite64be_lo_hi);
267 EXPORT_SYMBOL(iowrite64be_hi_lo);
268 
269 #endif /* readq */
270 
271 /*
272  * These are the "repeat MMIO read/write" functions.
273  * Note the "__raw" accesses, since we don't want to
274  * convert to CPU byte order. We write in "IO byte
275  * order" (we also don't have IO barriers).
276  */
277 #ifndef mmio_insb
278 static inline void mmio_insb(const void __iomem *addr, u8 *dst, int count)
279 {
280 	while (--count >= 0) {
281 		u8 data = __raw_readb(addr);
282 		*dst = data;
283 		dst++;
284 	}
285 }
286 static inline void mmio_insw(const void __iomem *addr, u16 *dst, int count)
287 {
288 	while (--count >= 0) {
289 		u16 data = __raw_readw(addr);
290 		*dst = data;
291 		dst++;
292 	}
293 }
294 static inline void mmio_insl(const void __iomem *addr, u32 *dst, int count)
295 {
296 	while (--count >= 0) {
297 		u32 data = __raw_readl(addr);
298 		*dst = data;
299 		dst++;
300 	}
301 }
302 #endif
303 
304 #ifndef mmio_outsb
305 static inline void mmio_outsb(void __iomem *addr, const u8 *src, int count)
306 {
307 	while (--count >= 0) {
308 		__raw_writeb(*src, addr);
309 		src++;
310 	}
311 }
312 static inline void mmio_outsw(void __iomem *addr, const u16 *src, int count)
313 {
314 	while (--count >= 0) {
315 		__raw_writew(*src, addr);
316 		src++;
317 	}
318 }
319 static inline void mmio_outsl(void __iomem *addr, const u32 *src, int count)
320 {
321 	while (--count >= 0) {
322 		__raw_writel(*src, addr);
323 		src++;
324 	}
325 }
326 #endif
327 
328 void ioread8_rep(const void __iomem *addr, void *dst, unsigned long count)
329 {
330 	IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
331 }
332 void ioread16_rep(const void __iomem *addr, void *dst, unsigned long count)
333 {
334 	IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
335 }
336 void ioread32_rep(const void __iomem *addr, void *dst, unsigned long count)
337 {
338 	IO_COND(addr, insl(port,dst,count), mmio_insl(addr, dst, count));
339 }
340 EXPORT_SYMBOL(ioread8_rep);
341 EXPORT_SYMBOL(ioread16_rep);
342 EXPORT_SYMBOL(ioread32_rep);
343 
344 void iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
345 {
346 	IO_COND(addr, outsb(port, src, count), mmio_outsb(addr, src, count));
347 }
348 void iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
349 {
350 	IO_COND(addr, outsw(port, src, count), mmio_outsw(addr, src, count));
351 }
352 void iowrite32_rep(void __iomem *addr, const void *src, unsigned long count)
353 {
354 	IO_COND(addr, outsl(port, src,count), mmio_outsl(addr, src, count));
355 }
356 EXPORT_SYMBOL(iowrite8_rep);
357 EXPORT_SYMBOL(iowrite16_rep);
358 EXPORT_SYMBOL(iowrite32_rep);
359 
360 #ifdef CONFIG_HAS_IOPORT_MAP
361 /* Create a virtual mapping cookie for an IO port range */
362 void __iomem *ioport_map(unsigned long port, unsigned int nr)
363 {
364 	if (port > PIO_MASK)
365 		return NULL;
366 	return (void __iomem *) (unsigned long) (port + PIO_OFFSET);
367 }
368 
369 void ioport_unmap(void __iomem *addr)
370 {
371 	/* Nothing to do */
372 }
373 EXPORT_SYMBOL(ioport_map);
374 EXPORT_SYMBOL(ioport_unmap);
375 #endif /* CONFIG_HAS_IOPORT_MAP */
376 
377 #ifdef CONFIG_PCI
378 /* Hide the details if this is a MMIO or PIO address space and just do what
379  * you expect in the correct way. */
380 void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
381 {
382 	IO_COND(addr, /* nothing */, iounmap(addr));
383 }
384 EXPORT_SYMBOL(pci_iounmap);
385 #endif /* CONFIG_PCI */
386